Considerable progress was made this year towards the goal of greatly increasing the sensitivity of the 2,4-dinitrophenylhydrazine-based immunochemical assay for protein carbonylation. With new methods for tissue preparation, carbonyl derivatization, and immunochemical quantitation, we are able to determine the level of protein carbonylation in either the head or thorax of individual Drosphila. This was the level of sensitivity we had hoped to achieve, as it allows assessment of an individual organism's protein carbonylation.